Means for treating molding sand



` F. E. MCCABE MEANS FOR TREATING MOLDING SAND I May 12,- 1931.

Filed March 25.V 1927 2 Sheets-Sheet l nventoz May 12, 1931. F. E. MCCABE l 1,804,623"

MEANS FOR TREATING MOLDING SAND Filed March 25, 1927 2 sheets-sheet 2 Patented May 12, 1931 UNITED* @Persa-OFFICE FRANK E.

MEANsroiiprn-Enrme rrvr-OLDINGL SAND i Appncanontiea Maren as, i927. serial No. 178,252.

l This inventionhasto do, generally, with so-called @continuousff .foundry systems,

wherein quantity production'and uniformity of product are the essential objectives. In these systems, 'the moldingsand is'used over and over again, and the Vkeeping of the sand in'sprop'er condition at Lall times has proven a difficult problem. f This is of paraf mount importance, however, if castings-fof high quality and uniform ygrade are tobe produced. l

yIt is to the sand treatment in systems of the classfreferred to 'that Vmy invention particularlyv relates. f The retempering oi*v the sand is'ellectively accomplished by reconditioning apparatus that is in more 'or less generalv use; but it was learned from experience that -anessential lquality was lacling 'from the molding sand when it was returned from the recon ditioning apparatus to the flasks. This was due to the fact that the sand was continuously passed through a hopper or bin between the reconditioning apparatus and the molding machine, and a considerable part of the sand would stick to theV walls of the hopper or bin until it became so dry that it would cease to adhere to the walls and would fall in relatively large masses and be carried with the fresh sand to the molding machines. This destroyed the uniform character of the sand and resulted in the production of weak and inferior molds.

The main object of my invention is to providey a means and method for overcoming this diiiicultyv in a simple, efficient and economical manner and without slowing down or interrupting the operation of the system.

An arrangement whereby this object is attained lis illustrated diagrammatically in the accompanying drawings wherein Fig. 1 represents my improved sand handling and treating apparatus in side elevation; Fig. 2 represents an elevational view Vtaken as though looking from the right of Fig. 1; and Fig. 3 is a sectional plan on the line 3-3 of F ig. 2. Y

Structural details have been omitted from the drawings inasmuch as all the elements shown are jof well known construction, and practical proportions as to relative sizes of the several units of the system vhave been dis-v carded in orderVto emphasize thefmethodKA and more clearly' set out the sand handling and treating apparatus to which the inven-` tion is restricted. y.

ln foundry systems of the class referred' to, there are mold forming, mold pouring,

and4r shake-out stations, and mold or yfllaskv carriers are movable along a course or track through or-past said stations, successively.

An example of such a system may be :found inmy former'application Serial No. 57,333, i'iled September 19, 1925. It will be-seen by reference to said application that the sand is distributed by suitable conveyors'from the sand reconditioningapparatus to the mold` ing machines 'atjthe moldv forming station, i

and theysurplus sand'is recovered romthe m'oldfforming station, and also from the shakeout stationwhere the castings and sandlare separated-and returned to 7the rjeconditioning'apparatus. The same arrange-` ment is present in the case at hand. In Fig. 1 the mold vforming station is representedfby a: molding machine that is `designatedrA, and it will be Vnoted that there; is an'op'eningl af in *the ffloor a onf' which the moldinglmachine vstands through which sur` plus sandvis adaptedto fall to the lower horizontal run b of a'flight conveyor that'is designated 'generally bythe reference letter B- andwhichisof' rectangular form vand isl disposed in a' vertical plane. This flight conveyor is of standard constructionv and involves a seriesjof scrapers b which oper-` ategin troughs or casings.v A belt conveypr C,} u"fli"icl1`,receivesV sand from the shake-,out station orapparatus, alsojdischarges onto.` the rflower, rungbv of the conveyor B and thisy sand, with that recovered from the 'molding station, isy carried up the ascending run b3 to-` the upper horizontal runA b4. Thesand is dumpedv fthroughv anopening Zin the bottomfolthe trough kof` the .upper run b4 intoV the sand reconditioning apparatusjthat Vis designated D, :where new sand, binder, and

Messen, Vor ctEvnLAnn-ioriro, nssenoa To THE GRABLER MANUFACTUR- p ine eoMrANY, ycantavaInnen, onto, A coarona'iron or omo sand and the Whole is thoroughly mixed and tempered.

The reconditioned sand is discharged from the apparatus D onto the lower run e of a second flight conveyor E which carries the sand up an ascending run el to an upper horizontal run e2; Disposed below this 1,run are two bins or receivers F and G into which the sand is adapted to be discharged from the conveyor E. To this end openings e? and e4 are made in theb'ottomot the trough of the upper run e2 above the respective bins F and G, and the formerY opening is provided with a slide or gate e5.v When this slide or gate is open, all the sand is d'ischarged' throughy the opening e3@ into-thegbin F, but when the same is Closed, the' sand` is carried, pastk the openings;3 and isl precipitatedthrough the opening e* into the binCri. The bottoms of the bins F and- Grx areycon'sti tutedofl thegrespective belt conveyors f andA g, the latter, when operating, discharging directly into'the upper; run b4 of the conveyor. B, while the former conveyor fw hen operating',4` discharges onto a similar` con-- veyor ff which is. arranged transversely, of. the conveyor f and hasits discharge end in delivering relationto the, upper runof the conveyor E; in. advance ot the discharge point of the conveyor g. y

Itwill be'observed'that, asthe; parts are illustrated, the slideor gate e5 is closedand that the flight conveyor F is.A discharging the reconditioned sand-K into thev bien G;- Whilethe bin-G, isthusbeing'flled,.the bin Fis being emptied by reason @f the'fact that the conveyors f and. ff are in: operation which'- causes. the sand from Y the.y bin F- to I carried.- by the. conveyors just mentioned, and along the upper,l run b4 of the conveyor-.5 B. to. a chute.. 66 that` leadsto ,the mold .forms ngstation represented by; the jmoldijngf maf. chine A. Y Y

Asthe supply of sand withinnthe-V loi-n. E

is, exhausted; the belt conveyor issetginf.

operation, the conveyors. fV andv`V f are stopped, and the slide or gate e5 is opened; whereupon the sand fromtheA recQHditifonl` ing apparatus will be delivered to. the bin wherein itwill accumulate. until said. bin. is filled and whilezthe bin Gisrbeing emptied,v

yBy reason of this arrangement itwill be n seen` that each bin is entirely emptied; hef.

ffore anymore sandisfd'umped into it,`wh`ere fore the sand' adjacent the'walls of'A the bin, and' which has a tendency to adhere to said. walls, is not: permitted to remain in such inert condition long enough coV become dry; And the-withdrawing ofi the sandvV alterV nately from they two bins at comparatively-f brief intervals; insuresfsand ofluniformqual ity bei-ng. delivened; to.,A the:k moldingma-f (shines. at all times. v

Itgwll; be-understood that suitable; driving;

I mechanisms (not shown) aregemployedzfor;

operating the several conveyors, and the same may be supplied according to common mechanical practice.

Having thus described my invention, what I claim is:

1.4 In foundry apparatuswherein sand is separatedl from castings,I reconditioned and returned to a hopper at a molding station, a plurality of storage tanks adapted to hold reconditioned sand', means for selectively lilling said"` tanks. and means4 for selectively emptying said tanks into said hopper, said means and'said tanks being so arranged that the sand delivery, is. substantially continuous'and caking andd'rying of reconditioned sand isgprevented.

2. In... foundryA apparatus wherein sand is separated from castings4 at shake-out stationsi,re,conditioned and returned to ahopper. atgthe--moldingstation, re-conditioning apparatus, a, conveyor adaptedto' deliver usedlsand to said apparatus, aplurality of storagetanks, a conveyor for selectivelyy delivering` sand fromY said., reconditioning means yto said storagetanks, means. for4 selectively discharging said storage tanks; into said-r1 hopper, said conveyors, tanks and meansbeing so arranged that the sand delivery is substantially Vcontinuous and vcal?- ingandy drying ofl fre-conditionedV sand is prevented.

Infltestimony: whereof, hereunto alii'x signature. Y v

FRANK E. MCCABE. 

